It was the final day of a two-month trip to Europe. I was in London, and with all of my work behind me, I had the freedom to do whatever I wanted. So I decided to test my five free London audio tours in a citywide blitz spanning two neighborhoods, one church, and two museums. It ended up being a very entertaining and cheap day, proving that you don’t have to spend a lot of money to have a fulfilling experience in this pricey city.

In the morning, I bought a one-day, off-peak subway and bus pass (a great deal at about $10) and caught the Tube from my hotel in South Kensington to Westminster. Time management was key: My last stop, the British Library, closed at 6 p.m., but my off-peak transit pass wouldn’t let me start until 9:30 a.m.

My walk commenced on Westminster Bridge, featuring fantastic views of the London Eye Ferris wheel and Big Ben. As I strolled with earbuds in, the constant churn of London — tourists, professionals, big tour buses, taxis, and so on — was strangely more apparent. I noticed what a great percentage of people on the streets were also lost in their ‘buds.

Whitehall — London’s Pennsylvania Avenue — was as grand as ever. Stretching from Parliament Square to Trafalgar Square, Whitehall is lined with illustrious buildings and evocative monuments. Security was almost military, as guards with machine guns at the ready paced in front of the gate at No. 10 Downing Street, home of Britain’s prime minister. Wandering past war memorials like the Cenotaph, honoring those who died in World Wars I and II, I noticed that the monuments of London have never looked so good, having been spiffed up for last year’s Olympics.

I ended my walk at Trafalgar Square, London’s central meeting point, highlighted by the world’s tallest Corinthian column, topped with a statue of Admiral Horatio Nelson. From here, I strolled along the Strand. Once a high-class riverside promenade, back before the Thames River was tamed with retaining walls, this busy boulevard is now home to theaters and shops.

About 15 minutes later, I reached St. Clement Danes Church, the starting point for my City of London walk. The one-square-mile area known as The City once comprised the original walled town. These days, it’s consumed by the financial district and Christopher Wren churches.

After the Great Fire of 1666 devastated this area, King Charles II turned to Wren to rebuild 51 churches in The City (not all survive). Of these, Wren’s greatest creation was St. Paul’s Cathedral. Even today, you can see the view that Wren intended — the majestic 365-foot-high dome of St. Paul’s hovering above the hazy rooftops, surrounded by the thin spires of his lesser churches.

After touring St. Paul’s, I ate lunch at the Counting House, an elegant bank building converted into a fancy pub and popular with neighborhood professionals. Though not the most penny-pinching place for a midday meal ($20 with beer), I confirmed my feeling that, while there are plenty of cheap-and-cheery modern eateries in London, this is a great spot for a memorable lunch.

From The City, I hopped into a cab to the British Museum, thinking this would save me time. I was wrong. Traffic was slow, and the meter reached 12 pounds (about $15). Lesson learned: I could have gotten there faster with my transit pass.

The British Museum is hands-down my favorite museum in London. This chronicle of Western civilization houses Egyptian mummies, Assyrian lions, and a large hall featuring the best parts of the frieze that once ran around the exterior of Athens’ Parthenon.

From the museum, I caught a bus to the British Library. Here, in just two rooms, are the literary treasures of Western civilization, including the Magna Carta, da Vinci’s notebook, Shakespeare’s First Folio, and Lewis Carroll’s “Alice’s Adventures in Wonderland.” Perhaps the best thing about the British Museum and the British Library — they’re free (though donations are appreciated).

Sights closed, brain drained, I hopped the Tube and zipped back to South Kensington for dinner at the Anglesea Arms. This place is everything a British pub should be: musty paintings, old-timers, beautiful people backlit, dogs wearing Union Jack vests, a long line of tempting beer-tap handles, and flower boxes spilling color around picnic tables — perfect for warm summer evenings. For under $25, I got a delightful meal with beer — a great value when you consider the high cost of dining in London and the joy of immersing yourself in a neighborhood pub with quality food.

It was an exhilarating day — and not unreasonable for a first-timer to tackle. And it was affordable: The audio tours and museums were free, St. Paul’s cost $20, transportation $25, and my meals $45. The total: about $90 for a very full day in London.

IF YOU VISIT…

SLEEPING: With over-the-top formality and modern English decor, Number Sixteen is surrounded by the trendy shops and colorful restaurants of South Kensington — and it’s a short walk from Harrods (splurge, www.firmdalehotels.com). The Luna Simone Hotel offers fresh, spacious rooms in the upscale yet inviting Pimlico neighborhood, near Victoria Station (moderate, lunasimonehotel.com).

EATING: The Counting House serves pub grub, including homemade meat pies, in what once was a bank (50 Cornhill, tel. 020/7283-7123). The Anglesea Arms, with a great terrace surrounded by classy South Kensington buildings, serves freshened-up versions of traditional English cuisine (15 Selwood Terrace, tel. 020/7373-7960).

GETTING AROUND: London has an excellent subway (Tube) and bus system that can get you just about anywhere you need to go. Taxis are also great, as cabbies love to talk and give advice about the city.

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